PDF4Java Reference Documentation
com.o2sol.pdf4java.core.encodings Package / PDFCmapRange Class / compare Method
the first object to be compared.
the second object to be compared.
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compare Method
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Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.

In the foregoing description, the notation `sgn(`expression`)` designates the mathematical signum function, which is defined to return one of `-1`, `0`, or `1` according to whether the value of expression is negative, zero or positive.

The implementor must ensure that `sgn(compare(x, y)) == -sgn(compare(y, x))` for all `x` and `y`. (This implies that `compare(x, y)` must throw an exception if and only if `compare(y, x)` throws an exception.)

The implementor must also ensure that the relation is transitive: `((compare(x, y)>0) && (compare(y, z)>0))` implies `compare(x, z)>0`.

Finally, the implementor must ensure that `compare(x, y)==0` implies that `sgn(compare(x, z))==sgn(compare(y, z))` for all `z`.

It is generally the case, but not strictly required that `(compare(x, y)==0) == (x.equals(y))`. Generally speaking, any comparator that violates this condition should clearly indicate this fact. The recommended language is "Note: this comparator imposes orderings that are inconsistent with equals."

Syntax

    public int compare(
       java.lang.Object o1,
       java.lang.Object o2
    )

#### Parameters

o1
  the first object to be compared.
o2
  the second object to be compared.

#### Return Value

a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.
Exceptions

Exception | Description
--- | ---
java.lang.NullPointerException | if an argument is null and this comparator does not permit null arguments
java.lang.ClassCastException | if the arguments' types prevent them from being compared by this comparator.

See Also

#### Reference

PDFCmapRange Class
PDFCmapRange Members

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